Pressure carburetor and fuel-air ratio regulator



J. A. BASCLE Dec. 29, 1953 PRESSURE CARBURETOR AND FUEL-AIR RATIO REGULATOR Filed April 31, 1950 5 Sheets-Sheet 1 INVENTOR JOSEPH ALBON BASGLE C m ATTORNEYS Dec. 29, 1953 J BASCLE 2,664,279

PRESSURE CARBURETOR AND FUEL-AIR RATIO REGULATOR Filed April 51, 1950 5 Sheets-Sheet 2 JOSEPH ALBON BASOLE mwkiumm ATTORNEYS J. A. BASCLE Dec.29, 1953 PRESSURE CARBURETOR AND FUEL-AIR RATIO REGULATOR 5 Sheets-Sheet vL;

Filed April 31, 1950 ATTORNEY:

INVENTOR JOSEPI-I- ALqgu BASCLE BY w q E IOM Dec. 29, 1953 J. A. BASCLE 2,664,279

PRESSURE CARBURETOR AND FUEL-AIR RATIO REGULATOR Filed April 51, 1950 5 Sheets-Sheet 4 FIG.IO.

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, /02 JOSEPH A LBON BASCLE wilbmmmw w ATTORNEYS Dec. 29, 1953 J. BASCLE 2,664,279

PRESSURE CARBURETOR AND FUEL-AIR RATIO REGULATOR Filed April 51, 1950 5 Sheets-Sheet 5 J4 FIG. I2. 20 {a 27 ii i" 62 j!- INVENTOR JOSEPH ALBON BASCLE BY nuh' :0

ATTORNEYS .free "movement.

Patented Dec. 29, 1953 UNITED STATES PRESSURE CARBURETOR AND FUELPAIR RATIO. REGULATOR -The present invention relates to a: pressurecar- 'buretor and fuel-airratio regulator and has: for

an object to produce a fuel-pressure type carburetor primarily created and designed to function with: a fuel-air ratio regulator of thetype described in my prior co-pending application Serial No. 113,142, filed August 3-0, 1949, now Patent 2,523,550 dated September 26, 1950.

.Another object of the present invention is to provide a carburetor in which thecustomary Venturi throat is eliminated and in which a spinning difiuser is used to homogenize the fuelair mixture throughout the speed and power ranges of. the internal combustion engine which is being served bythe improved carburetor.

A further object of the invention is to provide an improved carburetor-regulator combination in which the liquid fuel is channeled and circuited to move upwardly from the supply pump tothe metering means in a stabilized and air- A still further object of the inventionis to provide an improved carburetor in which the fuel-air regulator body, and parts thereof, may

bevariouslyassembled to the carburetor shell without destroying ;the previously described features and functions, thereby allowing the carburetor to be mounted on the engine in updraft,

:downdraft or horizontal fashion.

Astill further object of the invention is to provide an improved carburetor capable of allof the previously described features and: functions and also having: the common features ofan accelerating pump, speed and mixture adjustments, and other conventional fittings of vpresent day, carburetors.

A still further object ofthe inventionis to provide certain improvements over the. regulator described and claimed in my priorcopending applicationaforesaid inorderto. make. the me more. adaptable to the improved carburetor and carburetorlshell asherein illustrated and described.

With the foregoingand other objects in view, theinvention will be more fully described hereinafter, and will' be more particularly pointed out in the claims appended hereto.

Inthe drawings, wherein the symbols. refer jto..,1ike or corresponding parts .lthroughout the several views,

an improved pressure carburetor and fuel-air ratiopregulatorconstructed in accordance with z the present invention.

Figure 2. isa perspective view. oftheimprove pressure carburetor and fuel-air ratio regulator taken i from the regulator side ofthe carburetor with-the-choke .control levershown in dotted lines.

Figure3. isa frontelevational view of the improved device withithe carburetor body arranged in downdraft vertical. position.

Figure. 4 is a view similar to Figure3- with the carburetor bodyinvertedto assumetheupdraft vertical position.

.Figure 5v is a fragmentary side elevationalview illustrating the adjustable limit --stop .for the throttle valve.

Figure 6 isawertical sectional view taken on ,an enlargedscale on the line -e-eor Figure 3.

. Figure .7 is a fragmentary vertical sectional view taken through the. accelerating. pump with the pumppiston inltheouter position and with the .coil spring compressed.

--Figure .8e-is a fragmentary vertical sectional view takenon the lines-8 of Figure 6 and. showof thediaphragmyalve andits fuel orifice.

Figure 1-0 is .a-top plan View of the improved device-with-partsbroken away and parts shown in. section andillustrates particularly the air bleedand idling controlneedle valve.

Figure 11 is a bottom plan view of the carburetor body showingthe spinner and its blades injbottom plan.

Figure 12 is azside elevational view of the improveddevice with parts broken away and, parts shown in. section with the carburetor body arrangedin a horizontal position and with the regulator. attachment... carried beneath the car bur tonmdr.

Figure .13, isafrag mary perspective view of one formiof-va.mainimetering needle valve em .pl yed- Figure llfis-ayperspective View or an improved form of spinner employed.

Fi ure'15-is--a-=-vertical section taken on the line M--M of Figure 13 and showing the spin- --ner :blade. constructiomiand J Figureildyis a fragmentary: section; taken on ltherlinei iii-M 6" in Figure 3.

9, downdraft air passage- 2 l therethrough which communicates with the atmosphere, usually throughan'air cleaner, at its upper end andwith the intake manifold of an internal combustion engne at its lower end. in this air passage 2! is the conventional pivoted butterfly throttle valve The carburetor body 2! is supported by a base flange 22 upon the intake man fold 2 (Figure l) of an internal combustion engine, the same being bolted to the manifold or otherwise secured thereto so that the air passage it communicates with the induction system of the en ne.

Extending across the air passa e M is a bridge 25 havin a fuel pa sa e 25. At its central or intermediate point the brid e 25 supports an enlar ed downwardly ext ndin boss 2? which is hollow and internally threaded and communicates at up er end throu h a port 28 with the fuel pa sage stud 25 is adapted to be screwed into the boss 2?: such stud proiecting upwardly from a stationary tubular spinner sup ort 38 into the lower end of which is removably fitted a retaining ring 3!. being held to the upport So as by set screws or other appropriate fastenings. The ring supports the ball bearin s 33 which provides for the anti-friction rotation of the hollow spinner shaft 25. These ball bearings 33 are arranged between the hollow spinner shaft 35 and the outer tubular wall of the sup ort 33. The ball bearings may be in any suitable number. two series of such bearings being shown with a spacing ring 3 5 therebetween.

At its lower end the hollow spinner shaft carries a streamline head as which is also tubular in prolon ation of the fuel passage which extends through the hollow spinner shaft 35. The lower nose of the head 36 is closed below the tubular spinner blades 37 which project out substantially radially from the head 35 and which internally are in communication with the internal tubular pa sage of such head 38 in order to receive the fuel supply therefrom. The blades 3? are suitably flattened or shaped whereby the downdraft air issuing downwardly through the passage 2! incident to the suction demands of the engine will impinge upon the upper surface of 1 the blades 3?, imparting to such blades and to the head 35 and shaft 35 a spinning or rotary motion. In the trail ng edges of the hollow spinner blades 37 are made numbers of di persion apertures 38 out through which the fuel will issue into the air stream moving downwardly through the air passage 9 i The downdraft air passage 2| is expanded laterally as indicated at 39 over a section which may in tiate above the bridge 25 and terminate below the spinner blades 37. Such section 39 affords an enlarged chamber of an expanded diameter over the normal diameter of other cross sectional parts of the downdraft air passage 2! for the purpose of securing a substantially constant cross sectional area of the downdraft passage 25 throughout its length; the expanded portion 39 being to compensate for the mass of constructions necessarily introduced into the a r passage by the bridge 25 and the spinner unit.

Below the spinner the air passage becomes a mixing chamber.

The spindle i! of the throttle valve 22 is journaled through the carburetor body 20 with its ends project'ng outward thereof, to receive fixedly thereon an operating arm 32 adapted to be connected to the accelerator and a stop arm 43. The latter arm 53 has at its upper end an inwardly projecting stop finger 4 arranged between two stop screws 45 and '26 which. areadjustably An externally threaded reduced mounted in outstanding bosses 4'! and 48 on the carburetor body 20.

The arms 42 and 33 are also utilized to connect with the ends of curved links as and 50. The links are swiveled connected to the arms by the pivots 5| and 52. The convergent ends of the l nks 49, 50 are swivelly connected at 53 and 5G to opposite ends of a cross head 55. A threaded opening 55 extends completely through the cross head 55 and is arranged to receive the threaded section 5'! of a fuel control or metering needle adjustably received in the bore 26 of the bridge 25. A cross slot es in the outer end of the needle is adapted to receive screw driver or other tool for rotating the needle to adjust the same axially inward and outward with respect to a metering jet. A look nut 59 threaded to outer secton 5! of the needle is adapted to bind against the cross head to hold the needle in adjusted position.

The needle is formed with a rounded bearing section 50 on which the same rotates in the cylindrical fuel passage 26, and having an O-ring 56 or some other sealing means fitted about the needle section 60 to prevent the escape of the liquid fuel.

The needle also includes a fiat or straight-line section (52 which with the cylindrical wall of the fuel passage 26 forms ducts along which the liquid fuel may pass to the port 28 and to the spinner.

The needle also includes a tapering inner section 63 which fits through the main jet or orifice to in a screw threaded plug 65 which is removably fitted in a screw threaded socket 86 in the outer wall portion of the carburetor body 29 in alignment with the bore 2E.

The usual vacuum spark control connection is provided at 6?. (Figure 10).

An air bleed channel #38 is made in the carburetor body 2G or in an outstanding rib thereof with its receiving mouth opening in the air passage 2! on the atmospheric side of the throttle valve 22 while the discharge end of this channel 58 communicates with the fuel bore 26 down stream of the jet orifice A screw fitted and adjustable tapered needle 19 governs the entrance of atmospheric air to the receiving mouth 69 and is held in adjusted position by the tension spring 7!. The bleed channel 63 may be drilled through the rib and the upper outer end of the channel subsequently closed ofi by a plug 12. (Figure 12) An auxiliary air channel 13 for idling adjustment is also provided in the carburetor body 20 or in an outstanding rib thereof having a screw fitted and adjustable tapered needle "M on the atmospheric side of the throttle valve 22 to govern the entrance of atmospheric air to the channel and the delivery of such atmospheric air to the vacuum side of the throttle 22 onwhich the lower end 'of the channel l3 opens. tension spring preserves the adjustment of the needl M. (Figure 6).

The tapering section 6-3 of the fuel control needle projects outwardly of the bore 26 and is received into a needle receiving chamber 76 forming part of the fuel passage complementary to the bore 26. Two vacuum ducts l? and 1'8 are made through the carburetor body 29, the inner ,ends of these ducts communicating with the vacuum space of the air passage 2 l. Either one of these ducts H or E8 is adapted to communicate with a vacuum duct 19 formed in a rib 80 of the accelerating pump body 8! which is carried by a mounting plat 82 adapted to be removably afnular chamber E25, ports i353 and to the interior of the pistons M9, 22. From the internal space of these pistons HS, 222 the fuel under the combined control of the pistons and conic section ill of the metering valve H6 will be allowed to pass into the fuel chamber [to at one side of the diaphragm lil'i. Such fuel under pump pressure will pass along the face of the diaphragm E6? to the ports le t and IE5. These ports pass the liquid fuel to the channels at and Hi l and to the port 98 through which the fuel flows to the annular chamber 9%. From the chamber 56 the fuel is forced through the port 9'? into the passage '53 and from the main carburetor orifice 65 the fuel in controlled volume is passed to the bore 2% and along the flat sides 52 of the metering needle to by which the fuel under pressure is forced through the port 28 and to the tubular shaft of the spinner. The fuel passes down into and through the tubular head 36 and into the tubular blades El by which the fuel is discharged through the apertures 38 to the descending air stream. The spinner moves through all cross sectional portions of the air passage '2! and due to the numerous apertures 33 extending over a major portion of the diameter of the air passage 2! and due to the fact that these perforations are constantly rotating in a number of concentric circles Within the air passage 2i the discharge of the fuel to the air stream is made at great numbers of different points. The apertures are of a pre-selected diameter. Preferably the diameter varies. The perforations of smallest diameter are at the outer ends of the blades El and the diameters are graduated inwardly toward the center at which latter point the perforations of larger diameter will occur. This arrangement will ensure adequate delivery of the fuel to all of the orifices irrespective of their positions from the center of the spinner. The distribution of fuel through these numerous orifices as at variously placed positions in the air stream will ensure to all parts of such air stream an adequate and substantially uniform supply of the fuel to the end that the ratio of the fuel to the air will be uniform and the resulting mixture substantially homogeneous throughout for better combustion.

The air passage 25 is of substantially uniform cross section throughout the carburetor which differs radically from conventional carburetors employing a Venturi throat. The Venturi throat is employed in order to pull the fuel into the air stream and also to accelerate the movement of the air past the fuel nozzles and jets. However, the venturi sacrifices the volumetric capacity of the carburetor to meet the complete suction demands of the engine at all times. In accordance with the present invention the substantial uniformity of cross section of the air passage 2i throughout clears the passage of any throttling or air checking obstructions except for the minor masses of the bridge 25 and the spinner unit, but these obstructions are offset by the widening of the air passage at 39. Then to compensate for the absence of the venturi the fuel is introduced not at one point as in the Venturi system but at a plurality of points crosswise of the entire air stream. Of course this discharge is aided by the fact that the fuel delivery is under pressure. The fuel moves at a large number of points concentrically into the air stream having the advantage over the Venturi system in producing volumetric efficiency of the carburetor. In the Venturi systom the fuel discharge into the air stream takes the form of a conical pattern. This pattern is affected by the velocity of the air stream inasmuch as the lines of fuel flow are forced inwardly reducing the area of the fuel cone when the velocity of the air exceeds the combined velocity and weight of the fuel movement. Then the fuel cone collapses and does not extend outwardly into the outer portions of the air stream which pertions are therefore starved proportionately to the collapse of the fuel cone. In the case of the Venturi system therefore the volumetric emciency of the carburetor is depreciated and in addition the combustible mixture particularly at the full throttle speed and power positions of the carburetor is deficient. Such combustible mixture is not wholly homogeneous and particularly is this so at the outer portions of the air stream which are not penetrated by the fuel liquid. This loss of efficiency in conventional carburetors is corrected in the present device in that the volumetric efilciency through the carburetor shell of the present invention is calculated to be raised to the point of straight tube air flow and the fuel diffusing method employed therein distributes the fuel throughout the entire air flow area; specifical y the velocity of the air in this instance does not tend to deflect or destroy the possibility of a completely homogeneous mixture.

The conventional carburetor owing to the fuel discharge arrangement requires the introduction of the fuel at a remote point from the manifold whereas in the present device the spinning diffuser is located very close to the base flange 23 and at an extremely low point in the air passage 2i so that the fuel and air combustible mixture promptly on its formation enters the manifold. At this lower point where the spinner diffuser is located the air flow is relatively straight and therefore the fuel flow is not subject to distortion or deflection.

In accordance with the present system the liquid fuel is pumped under pressure in a path which is generally upwards from the pump I32 except for certain portions of the channel as for instance the channel 99 may be horizontal, but no channel for the fuel extends downwardly and the great majority of the length of the passage is upwardly. Due to the upward flow of the liquid fuel the dispersal of the accumulating air is automatic and constant in process. fherefore the system cannot become air bound nor the fuel flow instable or intermittent. There is therefore secured a positive air flow and a positive fuel fiow at all times.

Moreover the cross section of the liquid fuel channel is substantially uniform in cross section throughout. This arrangement has the effect of causing the fuel sup-ply to the main carburetor jet 54 to be constant in pressure and volume.

To further aid in the final breaking up of the 'fuel particles the air passage 68 constantly introduces a portion of atmospheric air into the outwardly moving fuel stream on the downstream side of the jet orifice 64'; (See Figure 12).

With the engine cold, in starting, the choke knob I2? is first pulled out which shifts the pistons H9, I22 inwardly and opens the metering fuel port I [8 for the'purpose of'introduoing a rich mixture to the engine on starting. At the same time the accelerator is operated to open the throttle valve 22. The needle 6b is entrained through the links 59, 58 to move outwardly in the bore 26 proportionately to the opening of the throttle 22 so that main carburetor jet orifice B l is opened proportionately wider. as the throttle 22 is progressively opened. This entrainment produces a pro-selected fuel-air ratio mixture which in turn yields a combustible mixture proper for normal operation. This ratio may be changed or adjusted by backing off the lock nut 59 toward the needle til by means of a screw driver or other tool applied to the cross slot 58, after which the nut 59 is again tightened against the cross head 55 so that the proportion or ratio of the fuel to air is to be maintained throughout the speed range of the engine.

When the engine warms, the control knob I2"! is pushed in to restore the position of the fuel orifice M8 to the normal operating position.

For sustained power requirements of the engine, such as when accelerating or in hill climbing, the proportion of fuel to air is automatically increased under the action of the regulator. Since under these conditions there is a sudden rise in exhaust pressure in the exhaust manifold to which the exhaust chamber i i3 of the regulator is connected, such increment in pressure in the exhaust pressure chamber Ht of the regulator will flex the diaphragm it! in the direction of the pistons H9, H2. In thi movement the diaphragm lfi'i will carry the metering valve i i6 in an axial movement inwardly of the small cylinder [l9 thus shifting the conic section ill of the valve respectively to the fuel orifice H8, bringing a smaller cross sectional area of the tapered section lil within the orifice H3. Thus the fuel pump will be able to pass a greater volume of the liquid fuel into the liquid fuel chamber tilt of the regulator and on into the carburetor by the channels heretofore described. This increase in liquid fuel volume will be accompanied by an increase in pressure which will automatically enrich the fuel mixture for power requirements. Thus by the use of the exhaust pressure in the fuel-air ratio regulator and the entrainment of the fuel metering needle 60 with the butterfly valve 22 a cooperative control of the fuel air mixture is achieved throughout the speed and power requirements of th engine.

For sudden and intermittent enrichment of the fuel air mixture such as during accelerating action, a supplementary enrichment of the mixture is provided by the use of a vacuum actuated accelerating pump 3| wherein the pump plunger 9b is supplied with fuel on the discharge side and is subjected to vacuum influence on the opposite side. It is to be remembered that during normal load operation of the engine a high vacuum condition exists in the inlet manifold and under this influence the accelerating pump plunger 90 will be drawn outwardly by this condition Whereas under conditions of sudden acceleration it follows that a sudden drop or collapse of the vacuum will occur and in this manner the spring 9! forces the piston 90 against the body of fuel outwardly and forces an enriched supply of fuel mixture for accelerating purposes. It is pointed out that the A. C. type of diaphragm pump consists of a check valve which prohibits the reverse flow of fuel back into the fuel pump and therefore the discharging portion of fuel from the accelerating pump must necessarily come into the carburetor air stream.

The carburetor body 26 is rotatabl about the transverse axis which passes through the center of the bore 25 to bring the carburetor body to an upright or a relatively inverted position. In one of these positions the throttle valve 22 will be above the spinner in which case the deyice functions as a downdraft carburetor. In

id the other case the throttle valv 22 will be below the spinner and the device then operates as an updrait carburetor. In either of these two positlons the regulator and the accelerating pump assembly remains in the same position, the bolts tic, ill and iii; being removed and replaced after the carburetor body 20 has been changed to the desired position.' Therefore the port te l at the upper portion of the round fuel chamber tilt in the regulator (rig. 6) which port is uppermost, will naturally receive the bubbles of any air entrained 111 the liquid fuel which bubbles Will rise naturally through the liquid fuel in a vertical direction and pass out the uppermost port Hi4 and thence be evacuated through the channel 99.

However, when the carburetor body 20 is turned on its side to function as a horizontal system (see Fig. 12) the fuel-air ratio regulator attachment will he below the carburetor, in which case the port Hi5 will be uppermost and will naturally receive the portion of air ascending through the liquid fuel in the fuel chamber its. The air Will pass out the channel liifi.

When the carburetor body 20 i relatively reversed the vacuum ducts il '53 will change places. In the downdra'lt arrangement the duct 'li will register with the duct all Of the attachment. in the updraft arrangement the duct iii will register with the vacuum duct it of the attachment. (See Figures 3 and 4).

Referring more particularly to Figures 14 and 15, in one method of producing the spinner blade construction, a round cross-section hollow tube of substantially the same external diameter of the internal diameter of the cross opening through the spinner head 35 is entered snugly through this opening unt1l the central portion of the tube arrives in the opening with substantially equal end portions of the tube projecting beyond the opening at opposite sides of the spinner head. Thereupon by use of a special forming tool, the outer projecting end portions of the tube are flattened and slightly rotated in relatively opposite directions to produce the cross sectional form of Figure 15. In this figure the leading edge of the blade so produced is the upper enlarged round edge with the sides of the blade 3i tapering downwardly and rearwardly with respect to the direction of rotation to the lower trailing edge at which are produced the apertures 38. The blade 3'? at one side of the spinner head 35 is shaped revcrsely to its companion on the other diametric side of the spinner.

Although I have disclosed herein the best form of the invention known to me at this time, I reserve the right to all such modifications and changes as may come within the scope of the following claims.

What I claim is:

1. A carburetor comprising a body having a substantially vertically straight down-draft air passage open to atmosphere above and to the engine below, a bridge across the air passage having a fuel passage therein in communication with a source of fuel supply, a throttle above the bridge, and a spinner assembly below the bridge comprising a spinner support depending from said bridge, a hollow spinner shaft in open communication at its upper end with the fuel passage in said bridge and journalled to rotate in said support and having a stream-lined downwardly projecting head on its lower end extending below the support, and hollow fiat blades extend ng radially from said head in interior communication with the internal space of the hollow shaft and receivingfuel therefrom, said radial fiat blades inclined on their radial axesto intercept the current of air descending in said air passage, said hollow blades having dispersion aperturesin the upper faces of the blades against which the down-draft air impinges, said apertures being close to the trailing edges ofithe blades.

2, Acarburetor comprising a body havinga. downdraft air passage therethrough in communiw cation with the atmosphere at. its upper end and. with the engine suction at its lower end, said passage havingthree sections andbeingsubstantially straight in a vertical direction throughout. its length with an upper throttle section, anin- 15 termediate section of larger. diameter thanthat of the other sectionsand alower mixing .section I joined to' the intermediatev section by. a. downs. wardly narrowing portion, abridgeacross the air passage substantially between the. throttle. andintermediate sections and having afuel passage. in, communication with a ,source. of. fuel supply, a throttlevalvein the..throttle;.section, anda spinner assembly in the.intermediate.sec-.- tion comprising a support depending .from the. bridge, a hollow rotary spinnershaft.journalled. in said support in communication..at...its. upper end with the fuel passage in said bridge and have ing below the support a hollow, head externally. streamlined from a wide base downwardlyto a reduced rounded nose withthe streamlined head included within the downwardly narrowing portion of the air passage, and hollow fiat spinner, blades in communicationwith the internal spaces of the head and shaft and carried bysaid head within the confines of the downwardly narrowing portion, the fiat blades being inclined aboutradii, of the head with their upper air-receiving surfaces having fuel dispersion apertures near. the trailing edges of the blades.

3. A carburetor comprising a body having a down-draft air passage therethro-ugh in a substantially straight line open to atmosphere above and to engine below, a bridge across the passage having a fuel passage in communication with a source of fuel supply, a throttle in the air passage on the upstream side of the bridge, and. a spinner assembly on the downstream side of the bridge comprising a spinner hollow shaft and connected head, a support for rotatably jour- 5O nalling the shaft in dependent relation to the bridge with the upper end of the internal spacev of the shaft open to the fuel passage in the bridge, and spinner blades radiating from the head, said blades being flat and hollow and in- 12.. clined to radial axes which pass -substantally through the central axes of the blades so that upper sides of the blades are inclined to and presented to the downwardly moving air stream, said upper blade sides having fuel dispersion apertures therein upstream of the downwardly moving air stream in the air passage.

4. vA carburetor comprising a body having an air passage substantially straight in an approximately vertical direction from end to end open at its upper end to atmosphere and at its lower end to an engine induction system, a bridge across an intermediate part of the air passage having a fuel passage therein in communication witha source of liquid fuel supply, a throttle in the air passage upstream of the bridge, and .a spinner assembly downstream of the bridge comprising ahollow shouldered support depending from the bridge, a hollow spinner shaft received within the support and in communication with the. fuel passage in thebridge, spaced bearings between the shaft and support with the upper bearings fitted against the shoulder, a spacer between the bearings supporting the shaft from the lower bearings, a retainer member in the 1ower end portion of the support below th lower bearing, and hollow spinner blades carried by the shaft in communication with the interior fuel space of the shaft and having fuel dispersion apertures therein.

JOSEPH ALBON BASCLE.

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